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51.
The finite element method has become one of the most-used calculation procedures in various fields of engineering in recent years. Due to progress in hardware architecture and computer graphics, the efficiency of its application could increase decisively. Notably, the solution of complex problems would be unthinkable today without the availability of powerful graphic processors.

In connection with the development of the finite element system COSAR at the Technical University Magdeburg, various graphic processors were created. In this paper, these processors are introduced. Information is given about interactive techniques for the generation of finite element models, about checking procedures for complex 3D structures by graphical means, and about possibilities for result presentation with colored pictures. Requirements for hardware architecture and software tools in the field of graphical input and output are discussed.  相似文献   

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Presentation of 11 cases of retroperitoneal sarcoma. Mean time from the beginning of symptoms to diagnosis is 6 months. The primary complementary study is CT. Surgery was performed in all cases, using complete resection in 6 cases, and partial resection in 5. Ten patients relapsed. 9 of which were treated with surgical rescue, in one or more occasions; chemotherapy was added in 6 cases and radiotherapy in 7. Survival at five years is 68%, with a mean follow-up of 66 months.  相似文献   
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Chemical oxidation of multilayer graphene grown on silicon carbide yields films exhibiting reproducible characteristics, lateral uniformity, smoothness over large areas, and manageable chemical complexity, thereby opening opportunities to accelerate both fundamental understanding and technological applications of this form of graphene oxide films. Here, we investigate the vertical inter‐layer structure of these ultra‐thin oxide films. X‐ray diffraction, atomic force microscopy, and IR experiments show that the multilayer films exhibit excellent inter‐layer registry, little amount (<10%) of intercalated water, and unexpectedly large interlayer separations of about 9.35 Å. Density functional theory calculations show that the apparent contradiction of “little water but large interlayer spacing in the graphene oxide films” can be explained by considering a multilayer film formed by carbon layers presenting, at the nanoscale, a non‐homogenous oxidation, where non‐oxidized and highly oxidized nano‐domains coexist and where a few water molecules trapped between oxidized regions of the stacked layers are sufficient to account for the observed large inter‐layer separations. This work sheds light on both the vertical and intra‐layer structure of graphene oxide films grown on silicon carbide, and more in general, it provides novel insight on the relationship between inter‐layer spacing, water content, and structure of graphene/graphite oxide materials.  相似文献   
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High-tech companies in the volatile microcomputer industry are facing a growing population of informed and technically enlightened buyers who have a broad base of workstation hardware from which to choose. As the process of selecting workstations becomes more complex, decision support becomes critical to aid buyers in making intelligent choices. This article describes a decision support system that was developed to assist buyers of workstations in selecting equipment with the highest benefit-to-cost rating.  相似文献   
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Background  

Omnivorous diets are high in arachidonic acid (AA) compared to vegetarian diets. Research shows that high intakes of AA promote changes in brain that can disturb mood. Omnivores who eat fish regularly increase their intakes of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), fats that oppose the negative effects of AA in vivo. In a recent cross-sectional study, omnivores reported significantly worse mood than vegetarians despite higher intakes of EPA and DHA. This study investigated the impact of restricting meat, fish, and poultry on mood.  相似文献   
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